Technical Field
The field is safety precaution, and in particular, alarm detector.
Background Art
An alarm detector is, as a sensing and detecting device, used for detecting various abnormal situations as well as the intrusion behavior of an intruder. A number of locations in a variety of intelligent buildings and general buildings are in need of safety precaution, and these locations have a variety of purposes and requirements of safety precaution according to actual situations. Therefore, there exists a need for a variety of alarm detectors, such as a smoke detector, a temperature detector, a special gas detector and an intrusion detector and the like, to meet different requirements of safety precaution.
An alarm detector generally includes a sensor, a sensor base, a circuit board (such as a PCB circuit board) and a circuit cover plate. In this case, the sensor is a sensing device of the alarm detector, and the circuit board is a signal processing device of the alarm detector. The circuit board is provided with an alarm sounder for alarming.
The current alarm detectors usually use a buzzer as an alarm sounder, and some may use a speaker in place of a buzzer as the alarm sounder. However, no matter what kind of alarm detector is used, the sound intensity thereof is usually limited by a specific component and will not reach a higher volume; therefore, for some applications with special requirements, for example, waking up people in deep sleep by an alarm sound, etc., this may not be enough to meet these requirements.